The present invention relates to handles for manual actuation of mechanical devices. More particularly, the invention relates to lockout and disengagement features for a rotary handle.
Many types of mechanical devices use handles for manual actuation. A typical example is a valve that is opened and closed by manually rotating a handle. The handle is coupled to a driven element such as a valve stem or other actuator mechanism within the valve. The actuator mechanism transforms the rotary motion of the handle into a desired movement that opens and closes the valve. For example, a diaphragm valve may have a valve stem that is rotated directly by the handle. When the valve stem rotates, it causes a relative movement between the diaphragm and a valve seat to thereby open and close the valve.
In some applications it may be desired or required to be able to disable a rotary handle such as with a lockout device or to actually lock the handle against rotation. It may also be desirable or required to disengage the handle from the driven member with or without a locking or lockout feature.
To the accomplishment of the foregoing objectives, and in accordance with one embodiment of the invention, a rotary handle is provided that includes several aspects that can be used separately or in a variety of combinations. According to one aspect of the invention, a rotary handle coupling mechanism is provided that permits the handle to be coupled and uncoupled from a driven member by an axial translation or displacement of the handle. In one embodiment, the handle can be locked or placed in a lockout condition when the handle is in either or both of the two axial positions.
In accordance with another aspect of the invention, a rotary handle mechanism is provided that restricts the rotary handle to a predetermined angular orientation in order to move the handle axially. In one embodiment, the mechanism also prevents rotation of the handle when the handle is axially moved to a predetermined position. In accordance with yet another aspect of the invention, a rotary handle mechanism is provided that permits the handle to be aligned with any angular orientation at the time of assembly, for example to coincide with angular orientation of a driven member. In one embodiment, the rotary handle mechanism is used in combination with an actuator mechanism for a valve.
These and other aspects and advantages of the present invention will be apparent to those skilled in the art from the following description of the preferred embodiments in view of the accompanying drawings.